LSU AgCenter Engineer Discusses Grass Edger Options

Lawns grow very fast and very aggressively in the South. If they’re not edged back regularly, Southern lawn grass will grow right over sidewalks, driveways, flower beds and anything else in their way.

"In the northern United States where Kentucky bluegrass is the predominant species, edging is necessary only once or twice a year," says LSU AgCenter engineer Dr. Dick Parish. "In the Deep South, you will probably need to edge every couple of weeks."

"It is possible to edge with a shovel or a straight-blade edging spade," Parish says. "It will take a lot of effort, but it may be the best option for small projects."

He also points to non-powered rotary edgers as an alternative to powered edgers, which most people prefer.

Parish says the traditional tool for larger edging projects is a walk-behind edger. These machines have a steel blade rotating about a horizontal axis and are carried on a set of wheels. The wheels are run on the sidewalk or driveway and allow precise control of cutting depth. Power can come from a small gasoline engine or an electric motor.

The gasoline engine models have more power and allow more versatile operation than electric models, but they’re more expensive and require more maintenance.

"The electric models require dragging a cord around, but they’re inexpensive and low maintenance," Parish says. "Both of these edgers are versatile, easy to adjust and control, and do an excellent job."

Parish says a more recent development that is popular with grounds maintenance professionals is the stick edger.

"This is basically an edging head mounted on the end of a string trimmer engine and shaft," he says. "Because they typically have only one wheel to carry the edger and control depth, a stick edger requires more skill than a walk-behind edger, but it is a very simple tool that is easy to carry on a truck and very light to load and unload."

Parish says a professional with a stick edger can edge almost as fast as he can walk.

"If your stick edger is the same brand and engine size as your string trimmer, you can use one can of fuel mix for both and also stock interchangeable engine parts," Parish says.

He points out that some string trimmers have a powerhead with interchangeable tools to change between a string trimmer head and an edger head on the same engine and shaft.

"A good alternative for homeowners is to use a string trimmer for edging," Parish says. "Just hold the trimmer so that the line is spinning in a vertical circle. If you have only a moderate amount of edging to do and already own a string trimmer, this will be your best option."

Parish says a string trimmer is harder to control than a dedicated edger, since it has no wheels or guides. Thus, you may not end up with quite as professional-looking edges as with an edger.

"One other negative to using a string trimmer for edging is that edging burns up trimmer line much more rapidly than routine trimming," Parish says. "Running against concrete chews up line rapidly, necessitating more frequent feeding and replacement. Electric string trimmers may not have enough power for edging."

The engineer warns that any edger can throw gravel or other objects with considerable force.

"Be sure to wear eye protection and keep all bystanders well away while you’re working," he says. "The debris is thrown in only one direction, but you really have no choice about which way to aim the tool, since edgers have to be aimed in only one direction.

"An edger blade can be lethal," Parish adds. "Be very careful to avoid blade contact and keep children and pets well away from the blade. Shut off the engine and remove the spark plug wire or unplug electric edgers before working around the blade."

For related landscape topics, go to the LSU AgCenter Web site, www.lsuagcenter.com. Additional yard and garden information is available from an extension agent in your parish LSU AgCenter office.